The Chlorination of the Al13- Cluster and the Stepwise Formation of Its Intermediate Products, Al11-, Al9-, and Al7-: A Model Reaction for the Oxidation of Metals?

摘要

By allowing chlorine gas to flow over solid aluminum at temperatures above 100℃ and under standard pressure conditions, gaseous AlCl3 is formed: Al(s)+3/2 Cl2AlCl3(g). The experimentally determined reaction energy is -585 kJ mol-1. To understand the fundamental process of dissolving of a metal in an oxidizing atmosphere-this is analogous to dissolving a metal in aqueous acid-intermediate products of individual reaction steps on the metal surface have to be identified. Because of varying surface properties, however, it is difficult to study local (microscopic) reactivity on macroscopic metal surfaces. Naked aluminum (Aln) clusters, on the other hand, are well-defined molecular model compounds and as such are well-suited for such investigations. Furthermore, the reactions of Al13- with iodine and hydrogen iodide have recently attracted significant interest.